• Title/Summary/Keyword: Advanced imaging techniques

Search Result 105, Processing Time 0.025 seconds

FPCB-based Birdcage-Type Receiving Coil Sensor for Small Animal 1H 1.5 T Magnetic Resonance Imaging System (소 동물 1H 1.5 T 자기공명영상 장치용 유연인쇄기판 기반 새장형 수신 코일 센서)

  • Ahmad, Sheikh Faisal;Kim, Hyun Deok
    • Journal of Sensor Science and Technology
    • /
    • v.26 no.4
    • /
    • pp.245-250
    • /
    • 2017
  • A novel method to implement a birdcage-type receiving coil sensor for use in a magnetic resonance imaging(MRI) system has been demonstrated employing a flexible printed circuit board (FPCB) fabrication technique. Unlike the conventional methods, the two-dimensional shape of the coil sensor is first implemented as a FPCB and then it is attached to the surface of a cylindrical supporting structure to implement the three-dimensional birdcage-type coil sensor. The proposed method is very effective to implement object-specific MRI coil sensors especially for small animal measurements in research and preclinical applications since the existing well-developed FPCB-based techniques can easily meet the requirements on accuracies and costs during coil implement process. The performances of the coil sensor verified through $^1H$ 1.5T MRI measurements for small animals and it showed excellent characteristics by providing a high spatial precision and a high signal-to-noise ratio.

Evaluation of Clinical Effectiveness of 3D Digital Endoscopic Image (3차원 디지탈 내시경 영상의 임상적 효용성 평가)

  • Song, Chul-Gyu;Kim, Kyeong-Seop;Kim, Nam-Gyun
    • Korean Journal of Digital Imaging in Medicine
    • /
    • v.5 no.1
    • /
    • pp.26-31
    • /
    • 2002
  • This paper represents the design of 3D endoscopic video system in order to improve visualization and enhance the ability of the surgeon to perform delicate endoscopic surgery. Minimally invasive techniques have set new standards in all surgical may experience less post-operative discomfort, shorter hospitalization, and quicker recuperation. Finally, the aim of the present study was to determine the influence of 2D and 3D video imaging on defined tasks on a laparoscopic trainer.

  • PDF

Human Sense-Based Simulation-Experience Model for Interactive Art Production (인터랙티브 아트 제작을 위한 인간의 감각 기반 시뮬레이션-체험 결합 모델)

  • Liu, Ting-Ting;Lim, Young-Hoon;Paik, Joon-Ki
    • Journal of the Korea Convergence Society
    • /
    • v.12 no.11
    • /
    • pp.169-184
    • /
    • 2021
  • Recent advances in science and technology leveraged various artistic tools. Interactive art based on various media technologies became popular in a short period, and is widely appreciated as a new form of art. This new form of art has a different method of expression from traditional art such as painting or sculpture. It aims to strike a balance among the artist, audience, and piece of art through interaction between the work and viewers. Viewers can take part in the creation process, going beyond the conventional way of art appreciation. This paper analyzes interactive art production techniques based on human senses from the artist's perspective. "Simulation-experience model" will be suggested after looking at several example artworks. Charming, which was produced based on this model, will be introduced and its meaning will be analyzed. The objective of this paper is to predict the future of interactive art and changes in the art form by studying interactive art production techniques based on human senses. We believe that the prediction is helpful in understanding the artistic and technological value and the social influence of interactive art in the future.

Tomographic Imaging for Structural Health Monitoring Inspection of Containment Liner Plates using Guided Ultrasonic (유도초음파를 활용한 격납건물 라이너 플레이트 상시감시 모니터링 검사를 위한 토모그래피 영상화)

  • Park, Junpil;Cho, Younho
    • Transactions of the Korean Society of Pressure Vessels and Piping
    • /
    • v.16 no.2
    • /
    • pp.1-9
    • /
    • 2020
  • Large-scale industrial facility structures continue to deteriorate due to the effects of operating and environmental conditions. The problems of these industrial facilities are potentially causing economic losses, environmental pollution, casualties, and national losses. Accordingly, in order to prevent disaster accidents of large structures in advance, the necessity of diagnosing structures using non-destructive inspection techniques is being highlighted. The defect occurrence, location and defect type of the structure are important parameters for predicting the remaining life of the structure, so continuous defect observation is very important. Recently, many researchers have been actively researching real-time monitoring technology to solve these problems. Structure Health Monitoring Inspection is a technology that can identify and respond to the occurrence of defects in real time, but there is a limit to check the degree of defects and the direction of growth of defects. In order to compensate for the shortcomings of these technologies, the importance of defect imaging techniques is emerging, and in order to find defects in large structures, a method of inspecting a wide range using guided ultrasonic is effective. The work presented here introduces a calculation for the shape factor for evaluation of the damaged area, as well as a variable β parameter technique to correct a damaged shape. Also, we perform research in modeling simulation and an experiment for comparison with a suggested inspection method and verify its validity. The curved structure image obtained by the advanced RAPID algorithm showed a good match between the defect area and the shape.

Management for locally advanced cervical cancer: new trends and controversial issues

  • Cho, Oyeon;Chun, Mison
    • Radiation Oncology Journal
    • /
    • v.36 no.4
    • /
    • pp.254-264
    • /
    • 2018
  • This article reviewed new trends and controversial issues, including the intensification of chemotherapy and recent brachytherapy (BT) advances, and also reviewed recent consensuses from different societies on the management of locally advanced cervical cancer (LACC). Intensive chemotherapy during and after radiation therapy (RT) was not recommended as a standard treatment due to severe toxicities reported by several studies. The use of positron emission tomography-computed tomography (PET-CT) and magnetic resonance imaging (MRI) for pelvic RT planning has increased the clinical utilization of intensity-modulated radiation therapy (IMRT) for the evaluation of pelvic lymph node metastasis and pelvic bone marrow. Recent RT techniques for LACC patients mainly aim to minimize toxicities by sparing the normal bladder and rectum tissues and shortening the overall treatment time by administering a simultaneous integrated boost for metastatic pelvic lymph node in pelvic IMRT followed by MRI-based image guided adaptive BT.

Transmission Electron Microscopy Specimen Preparation for Two Dimensional Material Using Electron Beam Induced Deposition of a Protective Layer in the Focused Ion Beam Method

  • An, Byeong-Seon;Shin, Yeon Ju;Ju, Jae-Seon;Yang, Cheol-Woong
    • Applied Microscopy
    • /
    • v.48 no.4
    • /
    • pp.122-125
    • /
    • 2018
  • The focused ion beam (FIB) method is widely used to prepare specimens for observation by transmission electron microscopy (TEM), which offers a wide variety of imaging and analytical techniques. TEM has played a significant role in material investigation. However, the FIB method induces amorphization due to bombardment with the high-energy gallium ($Ga^+$) ion beam. To solve this problem, electron beam induced deposition (EBID) is used to form a protective layer to prevent damage to the specimen surface. In this study, we introduce an optimized TEM specimen preparation procedure by comparing the EBID of carbon and tungsten as protective layers in FIB. The selection of appropriate EBID conditions for preparing specimens for TEM analysis is described in detail.

Augmented Reality System using Planar Natural Feature Detection and Its Tracking (동일 평면상의 자연 특징점 검출 및 추적을 이용한 증강현실 시스템)

  • Lee, A-Hyun;Lee, Jae-Young;Lee, Seok-Han;Choi, Jong-Soo
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.48 no.4
    • /
    • pp.49-58
    • /
    • 2011
  • Typically, vision-based AR systems operate on the basis of prior knowledge of the environment such as a square marker. The traditional marker-based AR system has a limitation that the marker has to be located in the sensing range. Therefore, there have been considerable research efforts for the techniques known as real-time camera tracking, in which the system attempts to add unknown 3D features to its feature map, and these then provide registration even when the reference map is out of the sensing range. In this paper, we describe a real-time camera tracking framework specifically designed to track a monocular camera in a desktop workspace. Basic idea of the proposed scheme is that a real-time camera tracking is achieved on the basis of a plane tracking algorithm. Also we suggest a method for re-detecting features to maintain registration of virtual objects. The proposed method can cope with the problem that the features cannot be tracked, when they go out of the sensing range. The main advantage of the proposed system are not only low computational cost but also convenient. It can be applicable to an augmented reality system for mobile computing environment.

Single-Molecule Imaging Reveals the Mechanism Underlying Histone Loading of Schizosaccharomyces pombe AAA+ ATPase Abo1

  • Kang, Yujin;Cho, Carol;Lee, Kyung Suk;Song, Ji-Joon;Lee, Ja Yil
    • Molecules and Cells
    • /
    • v.44 no.2
    • /
    • pp.79-87
    • /
    • 2021
  • Chromatin dynamics is essential for maintaining genomic integrity and regulating gene expression. Conserved bromodomain-containing AAA+ ATPases play important roles in nucleosome organization as histone chaperones. Recently, the high-resolution cryo-electron microscopy structures of Schizosaccharomyces pombe Abo1 revealed that it forms a hexameric ring and undergoes a conformational change upon ATP hydrolysis. In addition, single-molecule imaging demonstrated that Abo1 loads H3-H4 histones onto DNA in an ATP hydrolysis-dependent manner. However, the molecular mechanism by which Abo1 loads histones remains unknown. Here, we investigated the details concerning Abo1-mediated histone loading onto DNA and the Abo1-DNA interaction using single-molecule imaging techniques and biochemical assays. We show that Abo1 does not load H2A-H2B histones. Interestingly, Abo1 deposits multiple copies of H3-H4 histones as the DNA length increases and requires at least 80 bp DNA. Unexpectedly, Abo1 weakly binds DNA regardless of ATP, and neither histone nor DNA stimulates the ATP hydrolysis activity of Abo1. Based on our results, we propose an allosteric communication model in which the ATP hydrolysis of Abo1 changes the configuration of histones to facilitate their deposition onto DNA.

MR spectroscopy using single-shot RF localization technique (단일 RF 펄스를 사용한 3차원 체적 선택 방법을 이용한 MR 스펙트로 스코피)

  • Rim, C.Y.;Chun, K.W.;Ra, J.B.;Cho, Z.H.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1989 no.05
    • /
    • pp.51-54
    • /
    • 1989
  • In last several years, a number of volume localization techniques, such as ISIS, VSE, SPARS and STEAM etc., have been developed for the MR spectroscopy. These localizing techniques, however, require application of several RF pulses for the 3-D volume selection and suffer from T1 and T2 decays due to relatively long RF excitation time. In this paper, we propose a single-shot RF pulse localization technique to achieve the localized 3-D volume selection. This technique combines the cylindrical volume selection technique with a radial gradient coil with single-shot RF pulse and the oscillating selection gradient technique, so thai it minimizes the volume selection time. We report some experimental results obtained with the proposed method which appears promising for 3-D volume imaging and localized spectroscopy.

  • PDF

Functional MRI Study on Perceiving Orthographic Structure and Simplified Semantic Pictures (의미론적인 단순화된 그림 및 표의문자를 인지하는 과정에 대한 fMRI 연구)

  • Kim Kyung Hwan;Lee Sung Ki;Song Myung Sung;Kwon Min Jung;Chung Jun Young;Park Hyun Wook;Yoon Hyo Woon
    • Investigative Magnetic Resonance Imaging
    • /
    • v.7 no.2
    • /
    • pp.93-99
    • /
    • 2003
  • The different perceiving patterns of each picture, alphabetic words and Chinese characters, were widely investigated psychophysically. The more precise localisation can be done in terms of brain activity us-ing functional image technique such as PET and fMRI recently, Until now, there was no fMRI study to make direct comparison between perception of single Chinese character and simplified pictures (pictograph). We have made direct comparison of these two components using modern magnetic resonance techniques. We cannot confirm the right hemispheric dominance for perception of single Chinese character and pictographs. These two kinds of perceiving pattern can be underlying different mechanism.

  • PDF